Receiving vehicle is 81 240d 4sp... Donor cluster is from later model 300d with tach 120mph speedo and mini clock... My question is the reserve light (fuel) stays on, and are the sending units compatable? The oil pressure line hooked up correctly, and is displaying pressure as should. The tach I will hook up later, and the clock seems interm. I am also sure I need to calibrate the speedo, but how? Last but not least, the coolant guage seems to work properly, but are the sending units compatable?...thank you...